Effect of cage level (tier) on the performance of White Leghorn chickens

Conflicting reports exist in the literature about the effects of cage level (tier) on laying hen performance. Results clearly indicate, under conditions of this study, that performance as measured by egg production, egg weight, and mortality significantly deteriorated in a linear fashion progressing from the bottom to the top in three and four tier cages. Causes may be related to fear associated with differences in light intensity or differences in exposure to visual stimuli between the tiers.